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Dick Smith joins lower immigration party

Dick Smith is no stranger to public affairs but, until now, the high-profile businessman has avoided joining a political party.

His first is Sustainable Australia, which wants to reduce the immigration intake to keep population growth sustainable.

The party says the businessman signed up after watching one of its campaign videos.

Sustainable Australia president William Bourke says Mr Smith, like the party, wants Australia's annual immigration intake dropped from a record of more than 200,000 to 70,000 to keep its population below 30 million.

"Like me, he is sick of politicians stuffing up and selling off our country," he said in a statement on Thursday.

Mr Bourke is confident the entrepreneur will help Sustainable Australia win seats in the NSW and federal parliaments.

The party, which was founded in 2010, says its goal to reduce immigration would not affect Australia's refugee intake of between 14,000 and 20,000 people.